This invention relates to a mould assembly for manufacturing components using Hot Isostatic Pressing, HIP. In particular, this invention relates to a reusable mould for manufacturing components using HIP.
HIP fabrication involves the consolidation of a metal or ceramic powder under high temperature and high pressure conditions. Typically, net-shape HIP processes use a machined consumable mild steel canister as a mould in which a powder in-fill is consolidated into a required component shape. After the HIP process is complete, the consumable canister is removed from the formed component by machining and pickling.
The use of consumable canisters is inherently time consuming and materially expensive as each manufactured component requires a new canister. Further, the pickling process requires highly caustic chemicals which have cost and potential safety implications for the technology.
The applicants have investigated the use of re-usable moulds in which a substantially incompressible mould is housed within a plain canister. The canister in this instance is still consumable, however, because the features are formed within a re-usable mould, the canister is simpler to design and manufacture.
The use of a reusable mould addresses many of the drawbacks of consumable canisters of the prior art. However, using reusable moulds provides new difficulties.